Dental restoration scalpel

ABSTRACT

A scalpel that safely and efficiently removes excess dental composite from the surfaces of teeth. A method for removing excess dental composite from a dental surface using this dental scalpel.

BACKGROUND Field of the Disclosure

The present invention relates to dental tools and more particularly to ascalpel suitable for safely removing residual or excess resin compositesor other dental restorative materials from the interproximal and othersurfaces of a tooth.

Description of the Related Art

The “background” description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as aspects of the description which may nototherwise qualify as prior art at the time of filing, are neitherexpressly or impliedly admitted as prior art against the presentinvention.

A dental restoration, such as a white dental filling, is formed in acavity in a tooth by applying a dental restoration material usually acomposite resin. Composite resins are generally applied to a cavity in athree-step process. First, the cavity is filled with a compositematerial, then the composite is polymerized, cured or hardened bysubjecting it to ultraviolet light, and finally, excess composite isremoved by scraping or carving it away from the tooth to provide auniform and smooth surface and to give the filled tooth a naturalappearance.

Excess composite resin remaining on a tooth after a filling is formedcan trap food particles, cause discomfort to the patient, or beaesthetically unacceptable. Thus, when removing excess composite, it isimportant to completely remove all of the excess, particularly along thegum line and from interproximal surfaces between teeth which aredifficult to safely access and clean with existing dental instrumentswhich are designed for other purposes such as soft tissue removal or theremoval of calculus/tartar from teeth.

Excess composite resin is typically removed from a tooth with the aid ofan instrument designed for another purpose such as a scaler orplaque-removing tool for removing dental plaque. Plaque-removinginstruments typically have a cylindrical handle with a dental pick atone end or have a single blade extending from a cylindrical handle formanipulating silver filling material. Neither of these types ofinstruments is well suited for removing excess hardened composite resinfrom interproximal surfaces of a tooth. Specifically, neitherincorporates a blade that is contoured for use on the curvedinterproximal surfaces of a tooth nor does either incorporate a beveledcarving edge disposed at an ergonomic angle with respect to the shaft orhandle of the dental instrument.

Further, neither type of instrument includes two blades disposed onopposite ends of the handle so that one blade is beveled and angled forergonomic use on one side of a tooth and the other blade is configuredand angled for ergonomic use on the other side of the same tooth. Forexample, U.S. Des. Pat. No. 435,293; U.S. Pat. Nos. 1,369,582; 5,816,806issued Oct. 6, 1998; U.S. Pat. Nos. 5,913,682; and 6,247,477 all teachdevices having a cylindrical handle with a curved pick extending fromone end. While the curved picks taught by these patents may be usefulfor removing dental plaque, they are not well suited for carving excesshardened composite from a top layer of a filled tooth to provide asmooth surface or for removing hardened composite resin frominterproximal or other tooth surfaces.

Moreover, each of the aforementioned patents teaches a curved pick thatis entirely disposed within the plane of the axis of the handle. Thesedevices are not designed for use at an angle that minimizes discomfortto the patient or for use on the right and left surfaces of tooth whichcurve in opposite directions.

Other dental instruments for cleaning teeth or dispensing a liquid agenton teeth are described by U.S. Des. Pat. No. 199,832; U.S. Pat. Nos.3,101,727; and 6; 526,993 and teach devices having an edged planarsurface extending from a handle or grip. While each device is intendedfor use in cleaning teeth or for dispensing a liquid agent on teeth,none of these incorporates a curved concave or beveled edge suitable forcarving hardened composite off of interproximal surfaces of a tooth.

Dental scaling instruments also do not effectively or safely removeexcess dental resin composites. U.S. Pat. No. 4,060,897 teaches a devicefor cutting and lifting dental restoration material and U.S. Pat. Nos.5,127,833 and 5,169,313 teach a device for scaling teeth thatincorporates a shaft to prevent contact between the sharp edge of thedevice and the patient's cheek or tongue. However, these devices, do notincorporate a blade contoured and beveled to carve hardened dentalcomposite from the interproximal surfaces of a tooth, nor do thesedevices incorporate two mirror-imaged blades extending from oppositeends of a cylindrical handle so that each blade is in a plane at anangle with the axis of the handle so as to provide a dental instrumentthat can be used to remove hardened dental composite from right and leftinterproximal surfaces or that conveniently can be used by eitherleft-handed or right-handed practitioners.

In view of the lack of dental instruments specifically designed tosafely, quickly, and efficiently remove hardened dental composite fromthe surfaces of teeth, the inventors sought to design an instrument thatwould solve the problems described above.

SUMMARY OF THE INVENTION

A scalpel that has a shaft with one working end having a blade, andpreferably with two working ends comprising concave blades one of whichis oriented to carve along a left side of a tooth and the other along aright side. The working end contains blade having its base or spineadjacent to or connected to a plate that is preferably arranged at asubstantially right angle to the blade forming a T shape. The blade issufficiently hard to remove residual dental restorative materials, suchas hardened dental composite resins, from the surface of teeth and issized to comfortably fit within the mouth of a patient. The scalpelincludes a plate which provides for better handling and application orpressure to the blade as well as serving a safety feature which preventsthe scalpel from deeply penetrating soft tissue. In some embodiments, aworking end may contain an abrasive end, such as a file, that is hardand abrasive enough to remove dental composite, such as one with anabrasive surface (e.g., coated or layered with diamond, cBN, carborundumor any material that is harder than the composite to be removed). Insome embodiments, a working end may contain an abrasive tip or surface,such as a file, to remove dental composite, such as one with an abrasivesurface (e.g., coated or layered with diamond, cBN, carborundum or anymaterial that is harder than the composite to be removed and preferablyless hard than tooth enamel).

After a dental procedure, such as filling a cavity with a compositeresin, the scalpel may be used by a dental practitioner to comfortably,conveniently, and efficiently shape, contour and remove residualhardened dental restorative material from the surface of teeth includingfrom interproximal surfaces, occlusal surfaces, as well as proximal anddistal lingual and buccal surfaces without excessive stretching of thepatient's lips and cheeks.

The following examples illustrate various aspects of the presentinvention. They are not to be construed to limit the claims in anymanner whatsoever. Nonlimiting embodiments of the invention include:

A scalpel, comprising a shaft and at least one working end connected tothe shaft, said working end comprising a blade having a spine adjacentto or connected to a plate, wherein the dental scalpel is of a sizesuitable for comfortably removing a dental restorative material on asurface of a tooth.

Usually, the dental instrument, or its individual components includingthe blade, plate and shaft, will be about the same size as that shown inFIG. 6 or 7 or within a size range of 0.5 to 1.5-times the size depictedin these figures or with the same or similar proportions to human teeth.This range includes all subranges and intermediate values such as 0.5,0.6, 0.7, 0.8, 0.9, <1.0, 1.0, >1.0, 1.1, 1.2, 1.3, 1.4, <1.5 and 1.5.

In some embodiments, the length of the blade will range from about 10-15mm, the height of the blade will range from about 2-5 mm, the thicknessof the blade will range from about 0.02 -0.04 mm, the length of theplate will range from 15-20 mm, the diameter of the plate will rangefrom 4-12 mm, the length of the shaft will range from about 6-24 cm andthe diameter of the shaft range from about 2-4 mm. The length andthickness of the shaft, overall length of the entire scalpel, or otherdimensions, are selected to provide durability, a secure grip, ease ofhandling, and maneuverability of the scalpel while in use.

A blade may be curved or have any configuration known in the dental orsurgical arts or those configurations described herein. Preferably, theblade is concave so as to conform to a convex surface of a tooth.

In some embodiments, the scalpel may be monolithic where the blade,plate and shaft form a single unit.

In most embodiments, the working end, such as either the blade or plate,or a unit containing both the blade and plate, is removable from theshaft, for example, via a blade holder as illustrated by FIGS. 1-3 and 5which depict a working end with a slot to receive a blade and plate.

The blade holder, which may be a slot or other mechanical connectionbetween the shaft and working end, is arranged so that a working end maybe exchanged with a new or different kind of blade or combination ofblade and plate. In some embodiments, the scalpel will have a singleworking end, however, preferably, the scalpel will have two workingends. For example, one working end may be configured to carve along aleft side of a tooth and the other to carve along the right side of atooth, so that the practitioner does not need to exchange tips, butmerely switch from use of one end of the scalpel to the other to carvealong the right and left surfaces of a tooth.

In some embodiments, the scalpel blade will have a left side bevel andin others a right side bevel so as to facilitate carving along eitherthe left or right side of a tooth; in others, the blade may be beveledon both sides. Preferably, when the scalpel has two working ends, theblade on one working end has a left side bevel and the blade on theopposite end has a right side bevel. This permits the practitioner touse a single scalpel to conveniently and comfortably remove dentalrestorative or resin from either side of a tooth.

In embodiments where a shaft has two working ends, the orientation ofthe blades on each end may be the same or different. For example, eachblade may be coaxial with the shaft or point upward or downward at thesame or a different angle with respect to the shaft. In someembodiments, the blade on one end will point upward and the blade on theother end downward. In other embodiments, the bevel on the blade will beon the same side of the shaft as the blade on the other end, in othersthe bevels on a cutting blade will be on different sides of the shaft.

One embodiment of the invention is directed to a dental carverconfigured for removing interproximal composite deposits. The carver hasan elongated handle with a curved blade attached to each of its twoends. Each blade is oriented at an angle relative to the handle so thateach blade may be easily manipulated in the mouth of a dental patientwith minimal discomfort to the patient. The cutting edge of one of theblades is oriented to carve along the left side of a tooth when theblade is inserted into a patient's mouth, and the cutting edge of theother blade is oriented to carve along the right side a tooth wheninserted into a patient's mouth. With the cutting edges oriented inopposite directions, the instrument can be used in an ergonomic manneron either side of a given tooth by simply changing which end of theinstrument is inserted into the patient's mouth.

In a preferred configuration, the spine of the scalpel blade will adjointhe plate at a substantially perpendicular angle so that the blade formsa base of a T shape. In other embodiments, the blade may be oriented atless than, or more than, 90 degrees as with respect to the plate. Theconfiguration of blade, plate and shaft is selected so as to provide agreater nicety of balance and design and to reduce the risk of injury toboth the patient and practitioner during use of the scalpel and, forscalpels with replaceable working ends, during the exchange of a workingend.

In some embodiments, instead of a T shape adjoinder, the blade and platemay be adjoined via an inverted triangular support or any otherconnection that permits a practitioner to manipulate the blade or applyfinger pressure to the blade via the plate.

In some configurations two lateral sides of a plate may each be adjoinedto a blade to form an inverted triangle with two blades substantiallyintersecting at the lower vertex of the triangle. This configurationprovides more blade edge and can permit the same working end to be usedfor a longer time than a working end having a single blade.

The orientation of the working end can be measured with respect to thelongitudinal axis of the shaft by measuring the angle between alongitudinal axis of the plate aligned on the working end and thelongitudinal axis of the shaft. A working end may be co-axial with theshaft or handle of the scalpel or may be oriented upward or downward atan acute, right or obtuse angle, for example, it may be oriented upwardor downward (with respect to the direction the cutting edge of the bladeis facing) at an angle between 0, 10, 20, 22.5 30, 40, 45, 50, 60, 67.5,70, 80 or 90 degrees. In some embodiments the working end may assume anobtuse angle, such as 135 degrees, and form a U or V shape with theshaft. Such orientations may be used to access rear (buccal) surface ofteeth that may otherwise difficult to reach. This range includes allintermediate values and subranges. A dental practitioner may select anappropriate working end or blade angle depending on the location ofdental composite or restorative being removed.

In some embodiments, the blade, plate, and shaft are monolithic or theshaft and plate are monolithic, but not the blade.

In other embodiments the blade and plate are monolithic and may bereplaced or exchanged in the shaft as a unit.

In other embodiments, the blade and plate are separate from each otherand from the shaft and may independently be replaced.

In some embodiments, different shafts may be combined with particularkinds of replaceable blades or units of blades and plates. For example,shafts may have different lengths, diameters, balance points, orergonomic characteristics such as different handles, grips, textures orcoatings.

The invention is also drawn to a kit that offers the dental practitionera choice of scalpels with different features.

A kit may comprise two or more different shafts of different lengths,diameters, balance points, or ergonomic characteristics such asdifferent handles, grips, textures or coatings. A left- or right-handedpractitioner, a practitioner with small or large hands, or with a strongor delicate grip may select a suitable handle from amongst those in thekit.

A kit may provide two or more, or a series of, scalpels having differentshaped or sized blades, blades with different degrees of hardness, bladeorientations, or other physical characteristics. The scalpels may bemonolithic and two or more scalpels in the kit may have the same ordifferent blades, or the same or different spacing between the bevel orcutting edge of a blade and the plate. In embodiments where the blade,or a blade and plate unit, are replaceable, the kit may contain two ormore replaceable blades or blade and plate units with the same ordifferent features. The kit permits a practitioner to select a scalpel,blade, or plate with features suitable for carving a particular toothsurface while reducing the risk of accidental injury to the patient orthe practitioner.

A kit may also provide two or more, or a series of, different kinds ofplates, for example, rounded rectangular, oval, or triangular shapedplates, plates having different lengths, thicknesses, or surface areas,plates having either a concave or convex surface to facilitatemanipulation or the application of finger pressure to the scalpel, orplates having different ergonomic features such as non-slip or softsurfaces. These plates may form part of a replaceable blade and plateunit, or each type of plate may be incorporated into a particularmonolithic scalpel.

Another aspect of the invention is a method for removing hardened dentalcomposite or other dental restorative materials from the surface of atooth comprising contacting the hardened dental composite with a scalpelaccording to the invention.

In some embodiments, a dental composite may be contacted with asoftening agent or solution prior to removal of the composite by thescalpel of the invention.

The method is generally directed to human teeth, but may also be appliedto other mammals in which similar dental restorative procedures arepracticed, or in the production of dental prosthetics in which residualor excess composite dental resin or restorative is removed.

These and other objects of the present invention will become readilyapparent upon further review of the following specification anddrawings.

The foregoing paragraphs have been provided by way of generalintroduction, and are not intended to limit the scope of the followingclaims. The described embodiments, together with further advantages,will be best understood by reference to the following detaileddescription taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 depicts an embodiment of the dental scalpel of the invention. Theleft working end (400) has a blade beveled on its left side (30), whilethe right working end (500) as a blade beveled on its right side (30).The body (300) of the dental instrument may be held by the fingers andhand.

FIGS. 2A, 2B, 2C and 2D, respectively, depict four different views ofthe invention.

FIGS. 3A, 3B and 3C provide three views of one end of the dentalinstrument depicting blade tip (10), cutting edge (20), bevel (30),cheek (40) and plate (100). Together FIGS. 3A-3C depict blade tip (10),cutting edge (20), bevel (30), cheek (40), spine (50),support/neck/cheek (60), plate (100), plate neck (110), slot (200) andshaft (300).

FIGS. 4A and 4B show two different views of one end of the dentalinstrument with the blade beveled on the left side. Together FIGS. 4Aand 4B depict blade tip (10), cutting edge (20), bevel (30), cheek (40),and plate (100).

FIGS. 5A and 5B show the opposite working ends of a dental instrumentwith the blade beveled on either the left or right side.

FIGS. 6A and 6B depict how the oppositely beveled blades on each workingend of a dental instrument can be used to remove hardened dental cementfrom the right or left surfaces of a tooth.

FIGS. 7A, 7B and 7C depict particular embodiments of the invention.FIGS. 7A and 7B depict a dental scalpel with a replaceable blade andplate (100). FIG. 7C depicts a dental scalpel having a metal body andone working end.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Blade. The blade may be made of any medically acceptable material nothazardous for human health, such as stainless steel, carbon steel,surgical steel or other durable metal alloys. It may be made of orcontain titanium, nickel, vanadium or aluminum. In some embodiments, theblade will be subjected to a hardening treatment such as ionimplantation or hard-facing (deep nitriding) to improve durability andwear-resistance. In other embodiments the blade or the cutting edge maybe coated with a nickel-titanium coating, a nickel-titanium-nitridecoating, or another durable coating to retain a sharp edge and providecorrosion resistance. A non-disposable blade will be made of a materialthat does not substantially corrode or lose its sharp edge afterrepeated sterilization or that can be honed and sharpened between uses.Generally, a blade will be made of a material that is harder than thehardened dental composition being removed from teeth, for example itwill have a Vickers hardness of 50, 100, 150, 200 that is more than mosthardened dental composites, but the blade will have a Vickers hardnessless than that of tooth enamel. For safety, a blade may be covered by asheaf or cap or contained in wrapper.

In contrast to many scalpels using to remove soft tissue or to dentalscalers that remove calculus/tartar, the blade of the scalpel of theinvention is configured with a plate and blade support to reduce therisk of soft tissue injury and is made of or coated with a metal ormetal alloy (which may be tempered or ion-treated) so as to facilitatesafe removal of hardened dental composite. In contrast to dentalinstrument used to remove soft tissue and calculus/tartar, the scalpelof the invention needs to sharp and be able to exert high forcenecessary to remove hardened composite resins from enamel withoutdamaging a resin restoration.

A blade may have a variety of geometries including hollow ground, flatground, sabre ground, chisel ground, double bevel or compound bevel, andconvex ground geometries. Geometries include the S1-S7 and C1-C7geometries described by https://_en.wikipedia.org/wiki/Blade (lastaccessed Aug. 22, 2017) which is incorporated by reference. In someembodiments a blade will have a tip, cutting edge, bevel, cheek, spineand/or neck to facilitate attachment to a shaft or handle. In somepreferred embodiments, the blade will have a curvature similar to a No.12 surgical blade.

In some embodiments, the cutting edge will have a bevel on one sideonly; in others it will have a bevel on both sides. A cutting edge of ablade may be right- or left handed, for example, the blade may bebeveled on the left side providing a cutting edge on the left side ofthe blade (when viewed from the center of the shaft) or be beveled onthe right side providing a cutting edge on the left side.

In preferred embodiments, the blade will have a supportblade/cheek/neck, as depicted by (60) in FIG. 4 that is 2-4 mm deep,spanning the distance between the plate or blade spine and the bevel orcutting edge. In distinction to most surgical scalpels, this support incombination with the plate feature prevents the scalpel of the inventionfrom deeply penetrating soft tissues, thus substantially reducing therisk of lacerations to both the patient and practitioner. This supportmay range in depth from 1, 2, 3, 4, 5 mm or more depending on the degreeof safety desired, the kind of dental resin being removed, and theorientation of the tooth surface.

Plate. Forms part of a working end of the scalpel of the invention andallows a practitioner to apply force or pressure from a finger to theworking end to facilitate removal of a hardened dental composition froma tooth. Its length and width helps position the blade and preventforward or lateral blade slippage. The plate also provides for finecontrol over manipulation of the dental scalpel in the oral cavitycompared to conventional scalpels not having a plate, thus increasingpatient safety.

Preferably, the plate will have no sharp or pointed edges. In someembodiments, the plate will have a rounded rectangular, oval, ortriangular shape of sufficient area and distance from a handle portionof the shaft to permit a practitioner to apply finger pressure to theplate. In other embodiments, the plate may have a convex or concavesurface to facilitate manipulation or the application of finger pressureto the scalpel, for example, the plate may be made concave toaccommodate a fingertip or convex so as to permit a finger to applypressure via the plate at different angles by rolling a finger to oneside or the other of the plate. It may contain one or more ridges or besloped or banked toward or away from the center of the scalpel tofacilitate the application of reverse or forward pressure to thescalpel.

The plate may be textured, roughened, or coated to prevent slippage of afinger from it and thus provide for dexterous control of the scalpel. Inother embodiments, the plate will not be substantially larger than asize required for a practitioner to apply finger pressure through it tothe scalpel.

In many embodiments the plate and blade will be arranged in a T-shapewith the plate forming a supporting base for the blade, for example,where the spine of the blade contacts the plate.

In some embodiments, the plate and blade may be monolithic. Inembodiments where the blade is replaceable, the monolithic blade andplate are replaced as a unit. In other embodiments, the plate and bladeare not bound together and one or both may be separately replaced. Theentire scalpel or its various parts may be single- or multiple-use.

Shaft. A “shaft”, “handheld shaft” or “body” refers to an elongatedportion of the scalpel which is usually configured so that it may beheld in a hand. The more distal parts of the shaft from its center pointmay comprise a tapering waist, shoulder portion, or arm which formportions of, and help position, the scalpel blade. The shaft maycomprise one or more of metal (e.g., stainless steel, carbon steel,surgical steel, which may be coated with an alloy such asnickel-titanium; iron, titanium or aluminum or their durable alloys),plastic, ceramic or composite materials, for example, it may beconstructed from a composite resin containing metal, glass, carbon, orresin fibers or fillers. The shaft may include a recess, slot or otherblade holder which can receive a proximal end of a blade or bladeassembly, such as a unit comprising a blade and plate. Generally, theshaft will act as, or further comprise, a handle portion.

Portions of the shaft may be coated, texturized, fluted, roughened, orotherwise ergonomically shaped to provide for a firm grip and dexterouscontrol of the instrument. It may be coated with silicone, plastic, orother coatings to provide a soft and firm grip. The shaft can act as ahandle which in conjunction with the plate on the working end of thescalpel permits a practitioner to manipulate and/or apply pressure orforce to the working end to facilitate removal of hardened dentalcomposite by the blade. However, a shaft may also be configured to bemanipulated by a waldo, machine, dental equipment, or other devices.

Blade holder. Blade holders, including those used for scalpels, razorblades and craft knives (e.g., X-Acto™ knives), are known in the art andincorporated by reference to Karapetyan, U.S. Pat. No. 7,131,982 B2. Ablade holder may be arranged on one or both ends of the shaft of adental scalpel of the invention. A blade holder may allow rotation orpivoting of a blade that it holds and may have a locking mechanism suchas a slide-lock, snap fit, mating jaw, or chuck mechanism. In someembodiments, the blade holder will comprise a slot into which theproximal (non-cutting end) of a blade can be inserted or T-shaped orcross-shaped slots to accommodate insertion of a combination of bladeand plate.

In addition to a hole or slot to receive a blade and/or plate, a bladeholder may comprise a receiver to hold the blade inside the shaft and/ora securing member to secure or lock the blade and/or plate to the shaft.The blade holder permits replacement of blades that are dull orcontaminated with fresh or sterile blades, or the exchange of bladeshaving different physical or structural features, such as differentblade hardness or different blade shapes. In some embodiments the bladeholder permits a used or contaminated blade to fall freely from thescalpel without direct contact between the user and the blade.

A blade holder may further comprise an arm assembly that can positionthe blade or working end in different positions, such as at differentangles with respect to the longitudinal axis of the shaft, or inretracted or in one or more operationally extended positions.

In some embodiments the working end is integral with the handle and ablade holder is not required, for example, for a disposable scalpel, theblade, plate and shaft may be monolithic and non-replaceable. Similarly,a reusable scalpel may have a monolithic blade, plate and shaft in afixed orientation.

Composite resin. A “dental composite”, “dental composite resin” or“dental restorative” includes synthetic resins which are used indentistry as restorative material or adhesives. Synthetic resins evolvedas restorative materials since they are insoluble, aesthetic,insensitive to dehydration, easy to manipulate and reasonablyinexpensive. Composite resins are most commonly composed of Bis-GMA andother dimethacrylate monomers (TEGMA, UDMA, HDDMA), a filler materialsuch as silica and in most current applications, a photoinitiator.Dimethylglyoxime is also commonly added to achieve certain physicalproperties such as flow ability. Glass ionomer cements are alsocontemplated. Further tailoring of physical properties of thesematerials may be achieved by formulating unique concentrations of eachconstituent.

A hardened dental composite or restorative refers to one that ispartially or fully hardened, for example, it may be substantiallycompletely hardened via polymerization or 10, 20, 30, 40, 50 60, 70, 80,95, or <100% hardened (this range includes all intermediate values andsubranges). However, in some embodiments, a hardened dental compositemay be softened by contact with a softener prior to its removal with thescalpel of the invention. Vickers hardness of hardened composite resinsmay range from about 40 to 80; see K. H. Al-Samadani, Journal ofContemporary Dental Practice, December 2016; 17(12):978-984,incorporated by reference.

Teeth surfaces. Interproximal surfaces occur between teeth. Buccalsurfaces face outward from the mouth, while lingual surfaces are thosebehind the teeth. Mesial surfaces are those closest to the median plane,while a distal surface is that opposite from the mesial surface.Occlusal surfaces appear on the top of teeth, such as the relativelyflat surfaces on top of molars.

Tooth enamel ranks 5 on Mohs hardness scale, has a Young's modulus of 83GPa and a Vickers hardness of about 250 to 360; see Staines, et al.(1981) “Spherical indentation of tooth enamel”. Journal of MaterialsScience 16 (9): 2551-2556, and Gutiérrez-Salazar' et al., Mat. Res.6(3), São Carlos April/June 2003, which are incorporated by reference.While conventional devices are hard enough to remove hardened composite,sometimes harder than enamel, they are not safe to soft tissues.

Carving and Contouring. Excess or residual dental restoration materials,such as composite resins often remain after a tooth is filed orrepaired. For example, many dental composite resins suffer fromextensive contraction during polymerization which affect marginalsealing of a restoration and can result in application of excess resin,especially when posterior teeth are restored. While current efforts arefocusing development of non- or minimally-shrinking dental compositescontaining spiro-orthocarbonates as additives to dimethacrylates orepoxy-base resins, and the production of alternative filler materialsfor ideal wear resistance and esthetics, there is still a need forshaping and contouring a restoration as well as for removal excess orresidual dental resin. In a preferred embodiment of the invention, ablade, such as concave blade shaped similarly to a No. 12 surgicalblade, which can conform to a convex interproximal surface of a tooth orrestoration, is used to shape, contour and remove excess compositeresin. Carving procedures may involve first carving distal, mesial,lingual, and facial convex surfaces using a scalpel according to theinvention, followed by carving adjacent marginal ridges and contactareas and embrasures. It may also involve as carving parallel to acavosurface margin. Carving procedures are described in more detail byWiland, U.S. Pat. No. 4,270,902, which is incorporated by reference.

Terminology. Terminology used herein is for the purpose of describingparticular embodiments only and is not intended to be limiting of theinvention.

The headings (such as “Background” and “Summary”) and sub-headings usedherein are intended only for general organization of topics within thepresent invention, and are not intended to limit the disclosure of thepresent invention or any aspect thereof. In particular, subject matterdisclosed in the “Background” may include novel technology and may notconstitute a recitation of prior art. Subject matter disclosed in the“Summary” is not an exhaustive or complete disclosure of the entirescope of the technology or any embodiments thereof. Classification ordiscussion of a material within a section of this specification ashaving a particular utility is made for convenience, and no inferenceshould be drawn that the material must necessarily or solely function inaccordance with its classification herein when it is used in any givencomposition.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

It will be further understood that the terms “comprises” and/or“comprising,” when used in this specification, specify the presence ofstated features, steps, operations, elements, and/or components, but donot preclude the presence or addition of one or more other features,steps, operations, elements, components, and/or groups thereof.

As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items and may be abbreviated as“/”.

Links are disabled by insertion of a space or underlined space into alink, for example, before “www” or after “//” and may be reactivated byremoval of the space.

As used herein in the specification and claims, including as used in theexamples and unless otherwise expressly specified, all numbers may beread as if prefaced by the word “substantially”, “about” or“approximately,” even if the term does not expressly appear. The phrase“about” or “approximately” may be used when describing magnitude and/orposition to indicate that the value and/or position described is withina reasonable expected range of values and/or positions. For example, anumeric value may have a value that is +/−0.1% of the stated value (orrange of values), +/−1% of the stated value (or range of values), +/−2%of the stated value (or range of values), +/−5% of the stated value (orrange of values), +/−10% of the stated value (or range of values),+/−15% of the stated value (or range of values), +/−20% of the statedvalue (or range of values), etc. Any numerical range recited herein isintended to include all sub-ranges subsumed therein.

Disclosure of values and ranges of values for specific parameters (suchas temperatures, molecular weights, weight percentages, etc.) are notexclusive of other values and ranges of values useful herein. It isenvisioned that two or more specific exemplified values for a givenparameter may define endpoints for a range of values that may be claimedfor the parameter. For example, if Parameter X is exemplified herein tohave value A and also exemplified to have value Z, it is envisioned thatparameter X may have a range of values from about A to about Z.Similarly, it is envisioned that disclosure of two or more ranges ofvalues for a parameter (whether such ranges are nested, overlapping ordistinct) subsume all possible combination of ranges for the value thatmight be claimed using endpoints of the disclosed ranges. For example,if parameter X is exemplified herein to have values in the range of 1-10it is also envisioned that Parameter X may have other ranges of valuesincluding 1-9, 2-9, 3-8, 1-8, 1-3, 1-2, 2-10, 2.5-7.8, 2-8, 2-3, 3-10,and 3-9, as mere examples.

As used herein, the words “preferred” and “preferably” refer toembodiments of the technology that afford certain benefits, undercertain circumstances. However, other embodiments may also be preferred,under the same or other circumstances. Furthermore, the recitation ofone or more preferred embodiments does not imply that other embodimentsare not useful, and is not intended to exclude other embodiments fromthe scope of the technology.

As referred to herein, all compositional percentages are by weight ofthe total composition, unless otherwise specified. As used herein, theword “include,” and its variants, is intended to be non-limiting, suchthat recitation of items in a list is not to the exclusion of other likeitems that may also be useful in the materials, compositions, devices,and methods of this technology. Similarly, the terms “can” and “may” andtheir variants are intended to be non-limiting, such that recitationthat an embodiment can or may comprise certain elements or features doesnot exclude other embodiments of the present invention that do notcontain those elements or features.

Although the terms “first” and “second” may be used herein to describevarious features/elements (including steps), these features/elementsshould not be limited by these terms, unless the context indicatesotherwise. These terms may be used to distinguish one feature/elementfrom another feature/element. Thus, a first feature/element discussedbelow could be termed a second feature/element, and similarly, a secondfeature/element discussed below could be termed a first feature/elementwithout departing from the teachings of the present invention.

Spatially relative terms, such as “under”, “below”, “lower”, “over”,“upper”, “in front of” or “behind” and the like, may be used herein forease of description to describe one element or feature's relationship toanother element(s) or feature(s) as illustrated in the figures. It willbe understood that the spatially relative terms are intended toencompass different orientations of the device in use or operation inaddition to the orientation depicted in the figures. For example, if adevice in the figures is inverted, elements described as “under” or“beneath” other elements or features would then be oriented “over” theother elements or features. Thus, the exemplary term “under” canencompass both an orientation of over and under. The device may beotherwise oriented (rotated 90 degrees or at other orientations) and thespatially relative descriptors used herein interpreted accordingly.Similarly, the terms “upwardly”, “downwardly”, “vertical”, “horizontal”and the like are used herein for the purpose of explanation only unlessspecifically indicated otherwise.

When a feature or element is herein referred to as being “on” anotherfeature or element, it can be directly on the other feature or elementor intervening features and/or elements may also be present. Incontrast, when a feature or element is referred to as being “directlyon” another feature or element, there are no intervening features orelements present. It will also be understood that, when a feature orelement is referred to as being “connected”, “attached” or “coupled” toanother feature or element, it can be directly connected, attached orcoupled to the other feature or element or intervening features orelements may be present. In contrast, when a feature or element isreferred to as being “directly connected”, “directly attached” or“directly coupled” to another feature or element, there are nointervening features or elements present. Although described or shownwith respect to one embodiment, the features and elements so describedor shown can apply to other embodiments. It will also be appreciated bythose of skill in the art that references to a structure or feature thatis disposed “adjacent” another feature may have portions that overlap orunderlie the adjacent feature.

The description and specific examples, while indicating embodiments ofthe technology, are intended for purposes of illustration only and arenot intended to limit the scope of the technology. Moreover, recitationof multiple embodiments having stated features is not intended toexclude other embodiments having additional features, or otherembodiments incorporating different combinations of the stated features.Specific examples are provided for illustrative purposes of how to makeand use the compositions and methods of this technology and, unlessexplicitly stated otherwise, are not intended to be a representationthat given embodiments of this technology have, or have not, been madeor tested.

All publications and patent applications mentioned in this specificationare herein incorporated by reference in their entirety to the sameextent as if each individual publication or patent application wasspecifically and individually indicated to be incorporated by reference,especially referenced is disclosure appearing in the same sentence,paragraph, page or section of the specification in which theincorporation by reference appears.

The citation of references herein does not constitute an admission thatthose references are prior art or have any relevance to thepatentability of the technology disclosed herein. Any discussion of thecontent of references cited is intended merely to provide a generalsummary of assertions made by the authors of the references, and doesnot constitute an admission as to the accuracy of the content of suchreferences.

REFERENCES

Further background information and descriptive support for dentalrestoration materials and useful features of dental instruments may befound in one or more of the following references which are incorporatedby reference.

-   Gray, H. S., Gavin, J. B. The surface texture of trimmed composite    fillings. A scanning electron microscopy study. NZ Dent J. 1975;    71:139-145.-   Hietanen, J., Rantanen, A. V. Evaluation of different composite    finishing methods. Proc Finn Dent Soc. 1976; 72:11-18.-   Lutz, F. Beitrage zur Entwicklung von Seitenzahn-Komposits. KAR PAR    PZM Verlag, Zurich; 1980:1/7-75/7.-   McCabe, J. F., Caddick, R. J. The finishing of composite    restorations. Br Dent J. 1978; 145:101-104.-   Valcke, C. F. Some surface characteristics of composite resin    filling materials. J Dent Assoc S Afr. 1978; 33:21-27-   Porte, A. Cavity design for composite resin. (Others) AADR Program    and Abstracts, 1983 (Abstract no. 764).-   Oilo, G., Jorgensen, K. D. Effect of beveling on the occurrence of    fractures in the enamel surrounding composite resin fillings. J Oral    Rehabil. 1977; 4:305-309.-   Dennison, J. B., Craig, R. G. Physical properties and finished    surface texture of composite restorative resins. JADA. 1972;    85:101-108.-   Finger, W., Jorgensen, K. D. Polymerisations inhibition durch    Sauerstoff bei Kompositfullungsmaterialien and Schmelzversieglem.    Schweiz Mschr Zahnheilk. 1976; 86:812-824.-   Hannah, C. Mcd., Smith, G. A. The surface finish of composite    restorative materials. Br Dent J. 1973; 135:483-488.-   Heath, J. R., Wilson, H. J. Surface roughness of restorations. Br    Dent J. 1976; 140:131-137.-   McLundie, A. C., Murray, F. D. Comparison of methods used in    finishing of composite resin—a scanning electron microscopy study. J    Prosthet Dent. 1974; 31:163-171.-   De Gee, A. J., Ten Harkel, H. C. Abrasion of composite materials by    tooth brushing. J Dent Res. 1982; 61:571 (abstract no. 61).-   Bartenstein, U., Finger, W. Bestimmung der Oberflachengute von    Composite-Fullungsmaterialien. Dtsch Zahnaerztl Z. 1974; 29:276-282.-   Forsten, L. Fracturing of marginal enamel when finishing composite    fillings with rotary instruments. Proc Finn Dent Soc. 1977;    73:38-39.-   Tolley, L. G., Dennison, J. B., O'Brien, W. J. Surface finish of    composite materials. J Dent Res. 1977; 56:217 (abstract no. 663).-   Chandler, H. H., Bowen, R. L., Paffenbarger, G. C. Method for    finishing composite restorative materials. JADA. 1971; 83:344-348.-   Lutz, F., and Phillips, R. W. Classification of composite resin    systems and their evaluation. J Prosthet Dent, to be published.-   Lambrechts, P., Vanherle, G. Observation and comparison of polished    composite surfaces with the aid of SEM and profilometer. J Oral    Rehabil. 1982; 9:169-182.-   Nathanson, D., Dogon, I. L., Van Leeuwen, M. J. A comparison of a    new method for finishing composite restorations with conventional    techniques—in vivo study. J Dent Res. 1978; 57:367 (abstract no.    1170).-   Ferreira, M. R., De Wet, F. A. Effect of finishing agents on new    restorative resins: a SEM study. J Dent Res. 1982; 61:605 (abstract    no. 22).-   Louka, A. N., Stillwater, J. C. Effectiveness of different finishing    systems on composite resin surfaces. J Dent Res. 1982; 61:302    (abstract no. 1113).-   Johnson, L. N., Jordan, R. E., Lynn, J. A. Effects of various    finishing devices on resin surfaces. JADA. 1971; 83:321-331.-   Volchansky, A., Cleaton-Jones, P. Study of surface characteristics    of natural teeth and restorations adjacent to gingivae. J Prosthet    Dent. 1974; 31:411-421.

Sokal, R. R., Rohlf, F. J. Biometry. W. H. Freeman, San Francisco;1981:248.

-   Lutz F, Setcos J, Phillips R. New finishing instruments for    composite resins. J Am Dent Assoc. 1983; 107:575-580.-   Fruits T, Miranda F, Coury T. Effect of equivalent abrasive grit    sizes utilizing differing polishing motion on selected restorative    materials. Quintessence Int. 1996; 27:279-285.-   Oward S. Glazer, DDS, FAGD. Can an Instrument Make a Difference?-   Ivoclar Vivadent. Optra sculpt Pad: Modeling instrument for    composite filling materials. Amherst, N.Y.: Ivoclar Vivadent: 2005:    1-2.

1: A scalpel comprising: a shaft and at least one working end connectedto the shaft, said working end comprising a concave blade having a spineadjacent to or connected to a plate; wherein the blade is substantiallyperpendicular to the plate so that the blade forms a base of a T shape;and wherein the scalpel is of a size suitable for removing a dentalrestorative material on a surface of a tooth.
 2. The scalpel of claim 1,wherein the shaft is monolithic with the working end.
 3. The scalpel ofclaim 1, wherein the shaft comprises a blade holder for attaching theworking end.
 4. The scalpel of claim 1 that comprises a single workingend.
 5. The scalpel of claim 1 that comprises two working ends.
 6. Thescalpel of claim 1, wherein the blade has a left side bevel.
 7. Thescalpel of claim 1, wherein the blade has a right side bevel.
 8. Thescalpel of claim 1 that has two working ends one of which is configuredto carve along the right side or face of a tooth and the otherconfigured to carve along the left side or face of a tooth.
 9. Thescalpel of claim 1 that has two working ends, wherein the blade on oneend has a left side bevel and the blade on the opposite end has a rightside bevel.
 10. The scalpel of claim 1, wherein the blade comprises ablade support or blade cheek, which is between the plate and a beveledor cutting edge of the blade, that ranges from 1 to 6 mm in depth. 11.The scalpel of claim 1, wherein the blade comprises a blade support orblade cheek, which is between the plate and a beveled or cutting edge ofthe blade, that ranges from 2 to 4 mm in depth.
 12. The scalpel of claim1, wherein the working end is angled at an acute or right angle, asmeasured between the longitudinal axis of the plate on the working endand the longitudinal axis of the shaft blade is angled upward ordownward between about 0 and 135 degrees with respect to a longitudinalaxis of the shaft.
 13. The scalpel of claim 1, where the working endcomprises a blade that is angled upward or downward between about 15 and45 degrees with respect to a longitudinal axis of the shaft.
 14. Thescalpel of claim 1, wherein the blade, plate, and shaft are monolithic.15. The scalpel of claim 1, wherein the blade and plate are monolithicand are removably attached as a unit to the shaft.
 16. The scalpel ofclaim 1, wherein the blade or the plate are not monolithic with theshaft and are replaceable or exchangeable.
 17. A kit comprising two ormore scalpels of claim 1, wherein the blades, plates and shafts aremonolithic.
 18. A kit comprising a scalpel of claim 1 configured to holda replaceable blade or replaceable unit comprising a blade and plate,and at least one extra replaceable blade or replaceable unit comprisinga blade and plate.
 19. The kit of claim 18, wherein the at least oneextra replaceable blade or replaceable unit comprising a blade andplate, has a different blade hardness, different blade orientation withrespect to a longitudinal axis of the shaft, or a different blade designthan at least one other blade or replaceable unit in the kit.
 20. Amethod for carving or contouring a dental restoration or for removinghardened dental composite from the surface of a tooth comprisingcontacting the hardened dental composite with the scalpel of claim 1.